Thanks to Murry, it seems a whole new set of cool possibilities has
arisen for warming up our Wankels.

It's been a long time since I worked on diesel trucks, so I was'nt
aware
of Evans coolants. I just read through a couple long threads on an RX
forum debating the issue. For more than a year now I have read this
forum and have not heard of this stuff. If it's true the pressure
remains low, or even zero, then we should be chasing this one down
in a hurry. I have used water wetter for a long time in my porsches
and MX bikes. According to what I have read so far, I would have
saved myself, and a lot of other people, many headaches by using
Evans coolant products.

So what is it? Are the diesel guys wrong, and are the few RX
enthusiasts
similarly deluded, by promoting Evans products? Obviously, there are
a lot of advantages in using a coolant that does not vaporize within
the passages at or near zero psi; and what sort of pressure will we
see if we use it in our pressurized systems? If it does'nt vaporize,
or vaporizes very little, then we have a winner don't we?

The stuff's not that expensive. Who wants to be the first to try?

Search for Evans NPG+, on ebay.

Anyone have a good set of specs on this stuff?

Ed Carver

I know people have used it but someone mentioned the heat transfer
coefficient between coolant and metal is lower than ethylene glycol.
Evans coolant is mostly propylene glycol.
In order to properly test it one must have a "cylinder" head temp
sensor.

Paul Lamar



I suggest reading the Evans site. The NPG coolant was propylene
glycol. The
problem is it is more viscous and thus harder to pump. That along
with less
ability to transfer heat. The newer one, NPG+, IS A modified
ethylene glycol
base. It is less viscous than the propylene and pumps better. Part
of the
modifying makes it less poisonous which was one of the selling
points of the
propylene coolant.

Some of the local companies are using a coolant in their gas compressor
engines that I believe is propylene based. They seem to crack heads
a little
more frequently than regular coolant. They all can/will crack a head
once in a
while, but if the coolant is slightly more viscous there could be
spots that
it does not want to flow to very well. This would be a design flaw
compounded
by the coolant. I can not think of the name of this coolant right
now. They
get it in a barrel and pump it straight in.

Dale Davies

The viscous part is probably why the heat transfer coefficient is lower.
10 weight oil transfers heat better than 20 weight oil.

Paul Lamar

Evans coolant is an answer in search of a question. If the original
formula was so great, why did they change it?

Home made "Water wetter" is 1/2 teaspoon of Dawn dish-washing liquid.
Lynn E. Hanover